A split-type computer includes typically a host, a keyboard and a panel having a display function. In a mode where the panel is used, a battery is adopted to supply power to a panel subsystem. The capacity of the battery in the panel is limited due to a super slim and light structural dimension and design of the panel. A wireless display function, as the most power consuming function in the panel, occupies 45% of overall power consumption of the panel. In order to provide a sufficiently long battery lifetime, it is required to manage and control the power consumption of the panel. It is necessary to reduce the power consumption of the wireless display function.
The existing wireless display techniques, such as UWB, WIFI, Wireless HDMI and WHDI, are all designed for high definition (720p/1080p) wireless projection applications. Because these techniques support pictures of high resolution (1920*1080) and high frame transmission rate (30 fps or 60 fps), the wireless transmission maintains at a high data rate (100 Mbps-3.5 Gbps), resulting in a high transmission/reception power consumption (˜4.5 W@1080p/30 fps) in the wireless display function. Additionally, the existing wireless display techniques are designed for home high definition TV play applications. They operate in a real-time screen copy mode where a content currently displayed on the screen is captured and transmitted all the time without saving the power consumption. In a software-based compression, coding and transmission scheme in a WIFI display technique as an example, data compression is required, which increases a CPU load and significantly increases both a system power consumption at a transmitter and a decoding power consumption at a receiver and is thus undesirable for power-saving. Further, this technique has high requirements on system hardware at the transmitter (it requires at least a dual-core CPU at 1.6 GHz). The compression and decompression will cause a system latency of at least 100 ms and are not suitable for application scenarios having high real-time requirements (e.g., games). Although a high compression rate can reduce power consumption, it will result in a worse image quality and is thus not suitable for high definition applications. Without distinguishing usage scenarios and applications, it is not possible to effectively reduce the average power consumption during actual usage.
Further, in the prior art, buffers are incorporated at the transmitter and the receiver, which increases hardware costs. In the high definition display techniques, it is required to support high data rates. When there are many frames to be effectively buffered and a capacity of 2 Mb is required for buffering one frame, a large buffer will be necessary. Multi-frame buffering tends to introduce a large latency in a game for example and is not suitable for scenarios having high real-time requirements. In most of the existing wireless display techniques, a dumping scheme is used where each received frame will be transmitted, without considering any power management.
Therefore, the following defect in the prior art haven been found. Because the existing wireless display function supports pictures of high definition and high frame transmission rate, the wireless transmission needs to maintain at a high data rate, resulting in high power consumption in data transmission and reception. The prior art fails to consider how to save the power consumption.